GSSI SIR 20, User Manual

Page: 73 / 100

Geophysical Survey Systems, Inc. SIR® 20
Manual
MN92-078 Rev F 67
Chapter 5: Using a GPS with your SIR 20
Your SIR 20 is capable of attaching GPS coordinates to individual data profiles. This will allow you to
place the beginning and the end of your survey lines into a larger, real-world coordinate system provided
that you: 1) Survey in straight lines and 2) Have a GPS with sufficient accuracy for your application.
Attaching a GPS with its own data logger, such as the G30L available from GSSI, will allow you to
collect GPS data points with a much finer resolution. RADAN 6 will then be able to merge data files and
show coordinates with a GPR X, Y, and Z.
The GPS you do choose must have the following:
1. Provide data output through a serial (RS232) port.
2. Output data at a baud rate of 4800.
3. Output the NMEA GGA data string.
4. Capable of logging its own NMEA GGA info.
Note: GSSI only supports the G30L receiver/logger. All other GPS integrations are to be performed by
the customer.
Attaching a GPS
1
Plug in your GPS to the serial port on the back of the laptop and power up your GPS according to the
manufacturer’s instructions. Set your GPS to log the NMEA GGA data string and to communicate at
4800. If you are using the G30L, plug in the serial lead and plug in the PS2 power cord to the
provided USB adaptor and then plug into the USB port on the laptop.
2
Double-click the SIR 20 icon to open the collection program. Go to View > Customize SIRveyor and
ensure that the G30D is selected or Custom if you are using another GPS. Also check the output baud
rate. Click OK when finished.
Figure 71: SIRveyor customize screen.
3
Set up your data collection project as you normally would but be sure to click the Enable GPS button
in the Data Collection Mode window. The SIR 20 will communicate with the GPS and after a few
seconds you will see information appear at the right of the screen.